A technical college in the Dutch city of Leiden -- where armed police deployed outside schools early this week after an Internet threat of a mass shooting -- was evacuated because of a bomb alert on Friday, police said.
"The school (for further education) was evacuated after a bomb threat," police spokeswoman Welleke van Rantwijk told AFP, adding that there was "apparently no link to the threat" made earlier in the week.
"The school is now empty, the police are there investigating," she said.
Around 300 people were evacuated from the premises after the threat was made "a short time ago," Van Rantwijk said.
"I don't know how the threat was made," she said.
Authorities in Leiden had decided late Sunday to close secondary schools to thousands of pupils after a tip-off by Swiss police following the online threat.
"I will shoot my Dutch teacher and as many students as I can," said the anonymous message in English on the 4chan.org website.
"It's at a school in the Dutch city of Leiden" it said, chillingly adding "for more proof, I will be using a 9mm Colt Defender".
"Oh, and I'm using a proxy, the police is not gonna find me before tomorrow," the message ended.
City authorities lowered the threat level on Wednesday after tracing the Internet threat to Costa Rica.